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You searched for: Subject gases Remove constraint Subject: gases Subject ionization Remove constraint Subject: ionization
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1. The 3D quadrupole ion trap mass spectrometer as a complete chemical laboratory for fundamental gas-phase studies of metal mediated chemistry

Author:
Richard A. J. O'Hair
Source:
Chemical communications 2006 v. no.14 pp. 1469-1481
ISSN:
1364-548X
Subject:
catalytic activity; chemical bonding; chemical compounds; dissociation; gases; ionization; ions; mass spectrometry; spectrometers
Abstract:
... Electrospray ionization provides a “treasure trove” of metal containing ions whose fundamental reactivity can be studied via collision induced dissociation and ion–molecule reactions using the multistage mass spectrometry capabilities of the quadrupole ion trap mass spectrometer. Examples of metal mediated chemistry relevant to catalysis, C–C bond coupling, bioinorganic and supramolecular chemistr ...
DOI:
10.1039/b516348j

2. 4-Chloro-α-cyanocinnamic acid is an advanced, rationally designed MALDI matrix

Author:
Jaskolla, Thorsten W.; Lehmann, Wolf-Dieter; Karas, Michael
Source:
Proceedings of the National Academy of Sciences of the United States of America 2008 v.105 no.34 pp. 12200-12205
ISSN:
0027-8424
Subject:
bovine serum albumin; gases; gels; ionization; ions; mass spectrometry; models; peptides; proteomics
Abstract:
... Matrix-assisted laser desorption ionization (MALDI) has become an enabling technology for the fields of protein mass spectrometry (MS) and proteomics. Despite its widespread use, for example, in protein identification via peptide mass fingerprinting, a comprehensive model for the generation of free gas-phase ions has not yet been developed. All matrices in use today, such as α-cyano-4-hydroxycinna ...
DOI:
10.1073/pnas.0803056105
PubMed:
18723668
PubMed Central:
PMC2527889

3. Ab initio investigations on the gas phase basicity and nonlinear optical properties of FLiₙOH species (n = 2–5)

Author:
Ambrish Kumar Srivastava; Neeraj Misra
Source:
RSC advances 2015 v.5 no.91 pp. 74206-74211
ISSN:
2046-2069
Subject:
alkalis; energy; gases; hydroxides; ionization; optical properties; salts; synthesis
Abstract:
... Superalkalies, due to lower ionization potentials than alkalies, possess potential reducing capability and can be used in the synthesis of a variety of charge transfer salts. In order to check whether superalkali hydroxides are as basic as a typical alkali hydroxide, we have performed a systematic investigation on the hydroxides of small FLiₙ (n = 2–5) superalkali clusters. The equilibrium structu ...
DOI:
10.1039/c5ra14735b

4. Ab initio quantum chemical study on the mechanism of exceptional behavior of lysine for ion yields in MALDI--role of vibrational entropic contribution in thermally averaged proton affinities

Author:
Hatakeyama, Makoto; Tachikawa, Masanori
Source:
Journal of mass spectrometry 2011 v.46 no.4 pp. 376-382
ISSN:
1076-5174
Subject:
Gibbs free energy; desorption; gases; hydrogen bonding; ionization; lysine; mass spectrometry; temperature
Abstract:
... To elucidate the mechanism of the exceptional behavior of lysine for the ionization (protonation) yields in matrix-assisted laser desorption/ionization (MALDI) observed by Nishikaze and Takayama [Rapid Commun. Mass Spectrom. 2006, 20, 376], the temperature dependences of proton affinity (PA) and gas phase basicity for 20 amino acids are theoretically analyzed with correlated ab initio molecular or ...
DOI:
10.1002/jms.1903

5. Accuracy of Ion Mobility Measurements Dependent on the Influence of Humidity

Author:
Mayer Thomas; Borsdorf Helko
Source:
Analytical chemistry 2014 v.86 no.10 pp. 5069-5076
ISSN:
1520-6882
Subject:
analytical chemistry; gases; humidity; ionization; ions; spectrometers
Abstract:
... Measurements with sensor techniques in field analytical chemistry can be considerably affected by varying ambient conditions such as humidity. We systematically investigated the way in which ion mobility measurements are influenced by moisture. Both the peak positions of product ions within the spectrum and their relative abundance can vary depending on humidity. The transportation of humidity via ...
DOI:
10.1021/ac5007393

6. La- Activated Bicyclo-oligomerization of Acetylene to Naphthalene

Author:
Hewage Dilrukshi; Silva W. Ruchira; Cao Wenjin; Yang Dong-Sheng
Source:
Journal of the American Chemical Society 2016 v.138 no.8 pp. 2468-2471
ISSN:
1520-5126
Subject:
chemical elements; dehydrogenation; gases; ionization; naphthalene; spectroscopy
Abstract:
... We report the first example of metal-mediated acetylene bicyclopentamerization to form naphthalene in the gas phase. The bicyclic aromatic compound was observed in a complex with La. The La(naphthalene) complex was formed by the reaction of laser-ablated La atoms with acetylene molecules in a molecular beam source and was characterized by mass-analyzed threshold ionization spectroscopy. The bicycl ...
DOI:
10.1021/jacs.5b08657

7. Acylated glucosinolates with diverse acyl groups investigated by high resolution mass spectrometry and infrared multiphoton dissociation

Author:
Giuliana Bianco; Niels Agerbirk; Ilario Losito; Tommaso R.I. Cataldi
Source:
Phytochemistry 2014 v.100 pp. 92-102
ISSN:
0031-9422
Subject:
Barbarea vulgaris; dissociation; esterification; esters; gases; glucobrassicin; ionization; isomers; mass spectrometry; reversed-phase liquid chromatography; seeds; sinapic acid; substrate specificity
Abstract:
... With the aim of developing a procedure for detecting and identifying intact acylated glucosinolates (a-GLSs) found in trace quantities in natural plant samples, extracts of Barbarea vulgaris seeds were analyzed by reversed-phase liquid chromatography coupled with electrospray ionization and Fourier-transform ion cyclotron resonance mass spectrometry (RPLC-ESI FTICR MS). After a preliminary optimiz ...
DOI:
10.1016/j.phytochem.2014.01.010

8. Aliphatic and aromatic amines in atmospheric aerosol particles: Comparison of three ionization techniques in liquid chromatography-mass spectrometry and method development

Author:
José Ruiz-Jiménez; Sanna Hautala; Jevgeni Parshintsev; Totti Laitinen; Kari Hartonen; Tuukka Petäjä; Markku Kulmala; Marja-Liisa Riekkola
Source:
Talanta 2012 v.97 no. pp. 55-62
ISSN:
0039-9140
Subject:
aerosols; aromatic amines; atmospheric pressure; derivatization; gases; ionization; liquid chromatography; mass spectrometry
Abstract:
... A complete methodology was developed for the determination of ten aliphatic and nine aromatic amines in atmospheric aerosol particles. Before the liquid chromatography — tandem mass spectrometric separation and determination, the derivatization reaction of the analytes using dansyl chloride was accelerated by ultrasounds. From three different ionization techniques studied electrospray ionization w ...
DOI:
10.1016/j.talanta.2012.03.062

9. Ambient analysis by thermal desorption atmospheric pressure photoionization

Author:
Kaveh Jorabchi; Karl Hanold; Jack Syage
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.22 pp. 7011-7018
ISSN:
1618-2642
Subject:
atmospheric pressure; desorption; gases; helium; ionization; ions; mass spectrometry; nitrogen; non-polar compounds; spectrometers; thermal analysis
Abstract:
... Ambient mass spectrometry has attracted substantial attention in recent years. Among ambient ionization methods, thermal desorption ionization stands out because of two attributes: (1) simplicity, rendering the technique suitable for in-field applications, and (2) ability to couple with a variety of gas-phase ionization methods thereby broadening the range of molecules that can be analyzed with th ...
DOI:
10.1007/s00216-012-6536-z

10. An Ammonium Bicarbonate-Enhanced Stable Isotope Dilution UHPLC-MS/MS Method for Sensitive and Accurate Quantification of Acrolein–DNA Adducts in Human Leukocytes

Author:
Yin Ruichuan; Liu Shengquan; Zhao Chao; Lu Meiling; Tang Moon-shong; Wang Hailin
Source:
Analytical chemistry 2013 v.85 no.6 pp. 3190-3197
ISSN:
1520-6882
Subject:
DNA; acrolein; ammonia; ammonium acetate; ammonium bicarbonate; ammonium salts; carbon dioxide; detection limit; electrospray ionization mass spectrometry; formates; formic acid; gases; humans; ionization; isotope dilution technique; leukocytes; mutagenicity; nucleotides; pollutants; stable isotopes; stereoisomers; ultra-performance liquid chromatography
Abstract:
... Acrolein (Acr), a ubiquitous environmental pollutant, can react directly with genomic DNA to form mutagenic adducts without undergoing metabolic activation. To sensitively and accurately quantify Acr–DNA adducts (including structural isomers and stereoisomers) in human leukocytes, we developed an enhanced stable isotope dilution ultrahigh performance liquid chromatography (UHPLC)–tandem mass spect ...
DOI:
10.1021/ac3034695

11. Analysis of Intrinsic Peptide Detectability via Integrated Label-Free and SRM-Based Absolute Quantitative Proteomics

Author:
Jarnuczak Andrew F.; Lee Dave C. H.; Lawless Craig; Holman Stephen W.; Eyers Claire E.; Hubbard Simon J.
Source:
Journal of Proteome Research 2016 v.15 no.9 pp. 2945-2959
ISSN:
1535-3907
Subject:
gases; hydrophobicity; ionization; ions; liquid chromatography; mass spectrometry; models; peptides; proteome; proteomics; yeasts
Abstract:
... Quantitative mass spectrometry-based proteomics of complex biological samples remains challenging in part due to the variability and charge competition arising during electrospray ionization (ESI) of peptides and the subsequent transfer and detection of ions. These issues preclude direct quantification from signal intensity alone in the absence of a standard. A deeper understanding of the governin ...
DOI:
10.1021/acs.jproteome.6b00048

12. Analysis of a Common Cold Virus and Its Subviral Particles by Gas-Phase Electrophoretic Mobility Molecular Analysis and Native Mass Spectrometry

Author:
Weiss Victor U.; Bereszcazk Jessica Z.; Havlik Marlene; Kallinger Peter; Gösler Irene; Kumar Mohit; Blaas Dieter; Marchetti-Deschmann Martina; Heck Albert J. R.; Szymanski Wladyslaw W.; Allmaier Günter
Source:
Analytical chemistry 2015 v.87 no.17 pp. 8709-8717
ISSN:
1520-6882
Subject:
Human rhinovirus; capsid; common cold; desorption; electrophoresis; electrospraying; encapsulation; gases; genome; ionization; mass spectrometry; molecular weight; particle size; proteins; serotypes; virion; viruses
Abstract:
... Gas-phase electrophoretic mobility molecular analysis (GEMMA) separates nanometer-sized, single-charged particles according to their electrophoretic mobility (EM) diameter after transition to the gas-phase via a nano electrospray process. Electrospraying as a soft desorption/ionization technique preserves noncovalent biospecific interactions. GEMMA is therefore well suited for the analysis of inta ...
DOI:
10.1021/acs.analchem.5b01450
PubMed:
26221912
PubMed Central:
PMC4558612

13. Analysis of trace impurities in neon by a customized gas chromatography

Author:
Min Kyo Yin; Jeong Sik Lim; Dong Min Moon; Gae Ho Lee; Jeongsoon Lee
Source:
Journal of chromatography 2016 v.1463 pp. 144-152
ISSN:
0021-9673
Subject:
carbon dioxide; detection limit; detectors; gas chromatography; gases; hydrogen; industry; ionization; lasers; methane; neon; oxygen; semiconductors; thermal conductivity
Abstract:
... Excimer lasers, widely used in the semiconductor industry, are crucial for analyzing the purity of premix laser gases for the purpose of controlling stable laser output power. In this study, we designed a system for analyzing impurities in pure neon (Ne) base gas by customized GC. Impurities in pure neon (H2 and He), which cannot be analyzed at the sub-μmol/mol level using commercial GC detectors, ...
DOI:
10.1016/j.chroma.2016.07.057

14. Analyte-Tailored Controlled Atmosphere Improves Dielectric Barrier Discharge Ionization Mass Spectrometry Performance

Author:
Pascal Vogel; Ulrich Marggraf; Sebastian Brandt; Juan F. García-Reyes; Joachim Franzke
Source:
Analytical chemistry 2019 v.91 no.5 pp. 3733-3739
ISSN:
1520-6882
Subject:
atmospheric pressure; detection limit; gases; ionization; mass spectrometry; nitrogen; oxygen; perfluorocarbons; spectrometers
Abstract:
... Plasma sources in atmospheric pressure soft-ionization mass spectrometry have gained significant interest in recent years. As many of these sources are used under ambient air conditions, their interaction with the surrounding atmosphere plays an important role in the ionization pathway. This study focuses on the interaction between the plasma source and the surrounding atmosphere by connecting the ...
DOI:
10.1021/acs.analchem.9b00112

15. Analytical capabilities of surface-assisted laser desorption/ionization in the determination of low-molecular-weight volatile compounds

Author:
A. A. Grechnikov
Source:
Journal of analytical chemistry 2015 v.70 no.9 pp. 1047-1054
ISSN:
1061-9348
Subject:
desorption; gases; ionization; ions; volatile compounds
Abstract:
... Main approaches to the determination of low-molecular-weight chemical compounds by surfaceassisted laser desorption/ionization (SALDI) are considered. Analytes are adsorbed from a gas phase on the surface of a specially prepared solid-state substrate. Then, the surface is exposed to pulse laser radiation, which leads to ionization and desorption of ions to be detected with a mass analyzer. The fac ...
DOI:
10.1134/S1061934815090051

16. Antioxidant Properties of Kanakugiol Revealed Through the Hydrogen Atom Transfer, Electron Transfer and M2+ (M2+ = Cu(II) or Co(II) Ion) Coordination Ability Mechanisms. A DFT Study In Vacuo and in Solution

Author:
Tshepiso J. Tsiepe; Mwadham M. Kabanda; Kemoabetswe R. N. Serobatse
Source:
Food biophysics 2015 v.10 no.3 pp. 342-359
ISSN:
1557-1858
Subject:
enthalpy; gases; cobalt; aqueous solutions; aromatic compounds; copper; ionization; acetonitrile; electron transfer; dissociation; hydrogen; hydrogen bonding; antioxidant activity; metal ions
Abstract:
... DFT studies on the conformational and antioxidant properties of kanakugiol were performed to investigate factors that contribute to its conformational preferences and to elucidate its antioxidant properties and mechanisms. The antioxidant activity has been considered through the ability of kanakugiol to scavenge free radical species and through its ability to chelate metal ions. The antiradical ac ...
DOI:
10.1007/s11483-015-9397-0

17. Apparent activation energies of protein–protein complex dissociation in the gas–phase determined by electrospray mass spectrometry

Author:
Yelena Yefremova; F. Teresa I. Melder; Bright D. Danquah; Kwabena F.M. Opuni; Cornelia Koy; Alexandra Ehrens; David Frommholz; Harald Illges; Knut Koelbel; Frank Sobott; Michael O. Glocker
Source:
Analytical and bioanalytical chemistry 2017 v.409 no.28 pp. 6549-6558
ISSN:
1618-2642
Subject:
Gibbs free energy; activation energy; amino acids; dissociation; electrospray ionization mass spectrometry; gases; immunoglobulins; ionization; streptavidin
Abstract:
... We have developed a method to determine apparent activation energies of dissociation for ionized protein–protein complexes in the gas phase using electrospray ionization mass spectrometry following the Rice-Ramsperger-Kassel-Marcus quasi-equilibrium theory. Protein–protein complexes were formed in solution, transferred into the gas phase, and separated from excess free protein by ion mobility filt ...
DOI:
10.1007/s00216-017-0603-4

18. Application of ESI-HRMS for molybdenum speciation in natural waters: An investigation of molybdate-halide reactions

Author:
Duc Huy Dang; R. Douglas Evans
Source:
Talanta 2018 v.179 pp. 221-229
ISSN:
0039-9140
Subject:
bromine; electrospray ionization mass spectrometry; gases; halides; ionization; models; molybdates; molybdenum; pH
Abstract:
... High resolution electrospray ionization mass spectrometry (ESI-HRMS) was used to study the speciation of molybdate in interaction with halides (Cl, F, Br). Desolvation during electrospray ionization induced alteration of aqueous species but method optimization successfully suppressed artefact compounds. At low Mo concentrations, chloro(oxo)molybdate and fluoro(oxo)molybdate species were found and ...
DOI:
10.1016/j.talanta.2017.11.001

19. Application of FT-ICR-MS for the study of proton-transfer reactions involving biomolecules

Author:
Raczyńska, E. D.; Gal, J.-F.; Maria, P.-C.; Zientara, K.; Szelag, M.
Source:
Analytical and bioanalytical chemistry 2007 v.389 no.5 pp. 1365-1380
ISSN:
1618-2642
Subject:
amino acids; bioactive properties; capillary electrophoresis; dissociation; gases; high performance liquid chromatography; ionization; mass spectrometry; nucleic acids; nucleosides; photolysis; polynucleotides; polypeptides; polysaccharides; proteins; zwitterions
Abstract:
... Fourier transform ion cyclotron resonance mass spectrometry, combined with modern ionization (fast atom bombardment , electrospray ionization, matrix-assisted laser desorption-ionization), fragmentation (collision-induced dissociation, surface-induced dissociation, one-photon ultraviolet photodissociation, infrared multiphoton dissociation, blackbody infrared radiative dissociation, electron-captu ...
DOI:
10.1007/s00216-007-1508-4

20. Application of ion mobility-mass spectrometry to microRNA analysis

Author:
Kosuke Takebayashi; Kenji Hirose; Yoshihiro Izumi; Takeshi Bamba; Eiichiro Fukusaki
Source:
Journal of bioscience and bioengineering 2013 v.115 pp. 332-338
ISSN:
1389-1723
Subject:
gases; ionization; isomers; liquid chromatography; mass spectrometry; microRNA; pH; sequence analysis; solvents
Abstract:
... Liquid chromatography/mass spectrometry is widely used for studying sequence determination and modification analysis of small RNAs. However, the efficiency of liquid chromatography-based separation of intact small RNA species is insufficient, since the physiochemical properties among small RNAs are very similar. In this study, we focused on ion mobility-mass spectrometry (IM-MS), which is a gas-ph ...
DOI:
10.1016/j.jbiosc.2012.10.006